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    <title>determ</title>
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    <center>Scilab Function</center>
    <div align="right">Last update : 09/06/2006</div>
    <p>
      <b>determ</b> -  determinant of polynomial matrix</p>
    <h3>
      <font color="blue">Calling Sequence</font>
    </h3>
    <dl>
      <dd>
        <tt>res=determ(W [,k])  </tt>
      </dd>
    </dl>
    <h3>
      <font color="blue">Parameters</font>
    </h3>
    <ul>
      <li>
        <tt>
          <b>W</b>
        </tt>: real square polynomial matrix</li>
      <li>
        <tt>
          <b>k</b>
        </tt>: integer (upper bound for the degree of the determinant of W)</li>
    </ul>
    <h3>
      <font color="blue">Description</font>
    </h3>
    <p>
    returns the determinant of a real polynomial matrix 
    (computation made by FFT if W size is greater than 2*2).</p>
    <p>
      <tt>
        <b>res=determ(W [,k])</b>
      </tt>
      <tt>
        <b>k</b>
      </tt> is an integer larger than the actual degree of the determinant
    of <tt>
        <b>W</b>
      </tt>.</p>
    <p>
    The default value of <tt>
        <b>k</b>
      </tt> is the smallest power of 2 which is larger
    than <tt>
        <b>n*maxi(degree(W))</b>
      </tt>.</p>
    <p>
    Method (Only if W size is greater than 2*2) : evaluate the determinant of <tt>
        <b>W</b>
      </tt> for the Fourier frequencies
    and apply inverse FFT to the coefficients of the determinant.</p>
    <h3>
      <font color="blue">Examples</font>
    </h3>
    <pre>

s=poly(0,'s');
w=s*rand(10,10);
determ(w)
det(coeff(w,1))*s^10
 
  </pre>
    <h3>
      <font color="blue">See Also</font>
    </h3>
    <p>
      <a href="../linear/det.htm">
        <tt>
          <b>det</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="detr.htm">
        <tt>
          <b>detr</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="coffg.htm">
        <tt>
          <b>coffg</b>
        </tt>
      </a>,&nbsp;&nbsp;</p>
    <h3>
      <font color="blue">Author</font>
    </h3>
    <p>F.D.  </p>
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